.\" Written by Garrett Wollman
.\" This file is in the public domain.
.\"
.Dd November 13, 2019
.Dt LINSYSFS 4
.Os
.Sh NAME
.Nm linsysfs
.Nd Linux kernel objects file system
.Sh SYNOPSIS
.Bd -literal
linsysfs		/compat/linux/sys	linsysfs	rw 0 0
.Ed
.Sh DESCRIPTION
The
.Tn Linux
system file system, or
.Nm ,
emulates a subset of the
.Tn Linux
sys file system and is required for
the complete operation of some
.Tn Linux
binaries.
.Pp
The
.Nm
provides a two-level view of devices.
At the highest level, PCI devices themselves are named, according to
their bus, slot and function in the system hierarchy.
PCI storage devices are listed in the
.Pa scsi_host
class with a device symlink
to the PCI directories of the devices.
.Pp
Each device node is a directory containing some files and directories:
.Bl -tag -width ".Pa status"
.It Pa host
A place holder for storage host information.
.It Pa pci_id
A directory for the
.Pa pci_id
that contains either the device information or another directory structure
for a PCI bridge.
.El
.Pp
Each host node of scsi_host is a directory containing some files and directories:
.Bl -tag -width ".Pa proc_name"
.It Pa proc_name
The
.Tn Linux
registered driver name for these devices.
.It Pa device
A symlink to the PCI device directory.
.El
.Sh FILES
.Bl -tag -width ".Pa /compat/linux/sys/devices/pci0000:00" -compact
.It Pa /compat/linux/sys
The normal mount point for
.Nm .
.It Pa /compat/linux/sys/class/scsi_host
The storage host node.
.It Pa /compat/linux/sys/devices/pci0000:00
The PCI device hierarchy node.
.El
.Sh EXAMPLES
The most common usage follows:
.Pp
.Dl "mount -t linsysfs linsysfs /compat/linux/sys"
.Pp
where
.Pa /compat/linux/sys
is a mount point.
.Sh SEE ALSO
.Xr nmount 2 ,
.Xr unmount 2 ,
.Xr linprocfs 4 ,
.Xr linux 4 ,
.Xr pseudofs 9
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 6.2 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was derived from
.Nm linprocfs
by
.An Doug Ambrisko .
This manual page was edited by
.An Doug Ambrisko ,
based on the
.Xr linprocfs 4
manual page by
.An Garrett Wollman .
